Broaching machine



May 28, 1935-' M. ROMAINE ET Al. 2,002,924

BROACHING MACHINE ,357-, Y @M @f/Wm,

" i actor/M45 May 28, 1935. M. ROMAINE Er AL 2,002,924

BROACHING MACHINE Filed May 5, 1933 9 Sheets-Sheet 2 gmc/WM5 /V/LLAR OMA/NE E R WIN 6. KE HM May 28, 1935. M ROMAlNE Er AL 2,002,924

BROACHING ,MACHINE Filed May 3, 1955 9 sheets-sheet 3 May 28, 1935 A M. ROMAINE Er AL 2,002,924

BROACHING MACHINE fnl" 5 QAM/n4,

www

`May 28, 1935, M. ROMAINE Er' AL 2,002,924v

BROACHING MACHINE Filed May 3, 1933 9 SheelZS-Sheel'J 5 May 28, 1935. M. ol'MAlNE AL BROACHING MACHINE Filed May 3, 1953 9 Sheets-Sheet 6 IIIII/I nl fill!! l I 5 a l w w 3 hill: n

Iliff/viii j F916 w* May 28, 1935 M. RoMA|NE Er AL 2,002,924

BROACHING MACHINE Filed May 3, 1933 9 Sheets-Sheet '7 gmc/rm; Z 0 Mmm/@D Form/NE ERM/IN 6. KOE/1M @www May 28 1935- M. ROMAINE Er AL 2,002,924

BROACHING MACHINE Fild May 5, 1935 9 Sheets-Sheet v8 4-24 4x2-r 377 I ,l

:III ,lr 1 "El .May 28, 1935- M ROMAINE Er AL 2,002,924

BROACHING MACHINE Filed May 3, 1953 9 sheets-sheet 9 Patented May 1935 UNITED BROACHING MACHINE Millard Romaine, Cincinnati, and Erwin G.

t This invention relates machine tools and especially to improvements in breaching machines.

An object of this invention is the provision of 5 an improved breaching machinefor expeditious- 1y broaching work pieces.

Another object of the invention is the provision of a breaching machine that provides a plurality of work receiving stations which may be successively presented to the broaclr for o f,

eration thereon.

Another object of the invention is the pro- Vision of a breaching machine of the vertical type that is safe under all'conditions of operation and which is adapted to have the several parts thereof interlocked to prevent injury to the operator or cthe machine.

A further object of the vision of improved control means for operating the same which insures .a finer and more accurate control thereof.

It is also a'n object of this a broaching machine, all of the parts of which are hydraulically actuated in sequential order and winch is automatic in' operation whenA once set in motion.

Other objects and advantages of the present`` invention should be readily apparent by reference to the following specification considered in conjunction with the accompanving drawings, forming a part thereof, and it is to be understood that any modifications may be made in the exact structural details there shown and described,

within the scope of the appendedclaims, without I departing from or exceeding the spirit of the in-l vention. Y

In the drawings:

Figure 1 is a front elevation o f a broaching ma- .f chine embodying the improvements of this invention.

nism.

Figure 4 is a fragmentary sectional view taken on line 6-4 of Figure 1.

Figure 5 is a sectional view taken on line 5 5 of Figure 1.

Figure 6 is a fragmentary sectional view taken on line 6-'6 of Figure 5.

`Figure 7 is a sectional view taken online 1-1 of Figure 3.

Figure 8 is a fragmentary sectional view taken on line 8-8 of Figure 1.

ltoehm, Norwood, Ohio, assgnors to The Cincinnati Milling Machine Company, Cincinnati, Ohio, a corporation of Ohio Application May 3, 1933, Serial No. 669,209

35 Claims. (Cl. 90-33) to improvements in Figure 9 is a view partly in section and partly in elevation as seen from line 9 0 on Figure 8.

Figure 10 is a sectional view taken' on line iI-Il of Figure 8.

Figure 11 isa sectional view taken on line IVI--Il 5 of Figure 10.

Figure 12 is a sectional view taken online l2-I2 of Figure 1. I

Figure 13 is a fragmentary sectional view taken on line l3-I3 of Figure 12. l0

Figure 14 is a fragmentary sectional view taken on lineM-M of Figure 13.

Figure 15 is a view partlyin section and part-` ly in elevation vas seen from line I5-i5 on Fig-v ure 2.

Figure 16 ,is a Sview partly in rsection and partly in elevation as seen from line IB-IG on Figure 15. l

Figure 17 is a longitudinal sectional view through the reversing valve controlling the 20 movement of the ram.

Figure' 18 is a longitudinal sectional view through. the reversing valve controlling the movement of the work supporting` table.

Figure 19 is a plan view of one`of, the work 25 supporting and clamping fixtures as seen from line l9--l9 on Figure 1.

Figure 20 is an elevational view of the parts shown in Figure 19.

invention is the pro` invention to provide clamping xture as seen from line 2|-2I on Figure 19'.

Figure 22 is a fragmentary Vsectional view taken on line 22--22 of Figure 19.

Figure 23 is a fragmentary sectional view tak- 85 en on line 23-23 of Figure 22. l l

Figure 24 is a diagrammatic illustration of the several hydraulic circuits involved in the carrying forward of the invention.

Figure 25 is a fragmentary sectional view tak- 40 en on line 25--25 of Figure 2.

Figure 26 is a 'fragmentary sectional view taken on line 26-26 of Figure 19.

Throughout the several views of the drawings similar reference ,characters are employed to 45 denote the same Vor similar parts.

As was suggested above, the broaching machine of this invention is of the vertical type, that is, the broaching tools are actuated in a vertical direction relative to the work pieces. This machine in general comprises a bed or base on which is mounted a work supporting table adapted to have reciprocatory motion relative to the bed for positioning work pieces with respect to the tool or tools. The tablesupports Figure 21 is a sectional view through the work 30'- a pair of work clamping fixtures so that one fixture may be loaded while the work in the other iixture is being operated upon by the tools. Ris-' ing from the, bed is a column having formed thereon guideways for a ram to which the broaching tool or tools are attached. The bed and column support the various hydraulic control valves and other mechanisms for effecting and controlling the movement of the work supporting table and ram, as well as the prime movers for the hydraulic pumps. The cycle of the machine is such that initiation of the table in either direction initiates the cycle of movement of the machine which continues until the work piece is'nished and the tools again returned to their normal inoperative position. In addition, there is provided an interlocking or safety means which prevents the movement of the different parts until the movement of the preceding part has been' absolutely and definitely completed. l

Specifically the machine comprises a bed 38 having formed on its upper surfaceguideways 3| receiving similar ways formed on the lower surface of a work supporting table 32. Secured to the rear of the bed 30 and rising above it is a column 33 having formed along its forward face guideways 34 for a ram 35 which contacts therewith.

'I'he column 33 is provided with a plurality of compartments, the lowermost one, 36, see Figure 3, constitutes a chamber for the hydraulic medium, preferably oil, utilized in the operation of the various hydraulically actuated parts. Above the chamber 36 is a chamber 31, being separated by a web or wall 38. Secured to the web or wall 38 is a bed plate 39 supporting on one end,- thereof and partially exteriorly of the chamber 31 a prime mover 40, here shown as an electrical motor. is coupled through a coupling 42 with a. pair of pumps, indicated generally by the numerals 43 and 44. These pumps are standard commercial articles and are enclosed in a single casing or a pair of casings secured to one another. The pumps 43 and 44 are supported by a pedestal 45 integral with or secured to and extending upwardly from the bed vplate 39.

Above the chamber 31 the column 33 is provided with a chamber 46 being 'separate from the chamber 31 by a web or wall 41. Secured to opposite vertical walls of the chamber 46 are the control valve casings 48 and 49, one of which contains the reversing valve for controlling the movement of the ram and the other of which contains the reversing valve`for controlling the movement of the work' supporting table.

In practice the pumps 43 and 44 are connected `by suitable conduits extending into the tank within the chamber 36 for drawing oi the fluid therein and with additional conduits or pipes extending to the valves 48 and 49 within the chamber 46 and other valves which willbe subsequently described in detail.

The work supporting table 32, see Figures 2, 3, and 7, is provided on its left hand end with a lug 50 having formed thereinaa perforation through which extends the reduced end 5| of a piston rod 52. 'I'he piston rod 52 extends through a cylinder head and stumng box 53 into a cylinder 54 secured to the cylinder head. Interiorly of the cylinder 54 the piston rod 52 has secured to it a piston 55y and the cylinder 54 is closed at its other end by a. head 56. The cylinder is secured to a pad or lug 51 provided on the forwardl face 'I'he shaft 4| of the motor 4|)l of the column 33 just above the bed 30. From this it will be seen that if hydraulic pressure is introduced on one or the other side of the piston 55 the table 32 will be moved relative to the column 33 and bed 30. The hydraulic mechanism for controlling and supplying the uid will be described in detail later.

On the upper surface of the table 32 there is secured a pair of work supporting and clamping fixtures 58 and 59, see Figure 1. 'I'he table 32 is adapted to have one of its fixtures beneath the ram while the other is beyond the ram being loaded and in order to properly position the work with respect to the tools the table has secured to its rear surface a block 60, opposite faces of which are adapted to engage adjustable stops. The adjustable stops are similar in all respects and it is believed that a description of one of them will suilice for the other. This stop, see Figure '1, comprises a screw 6| threaded through a lug 62 of a bracket 63 secured to the face of the column above the bed. The abutment screws are locked in position by lock nut 64. From this it will be seen; that the work fixtures 58 and 59 are each accurately aligned with the broach ram.

Referring now to Figure 24, it will be noted thatthe pump 43 is indicated as a larger pump than 42 and inlact pump 43 is a large volume, high pressure pump while the pump 42 is a low volume, low pressure pump. fFrom the pump 43 extends a suction pipe 65 which 4terminates in the tank 66 which is disposed'in the column chamber 36. kFrom the other side of the pump 43 is a pipe or conduit 61 having branch conduit 68 extending therefrom. The conduit 68 terminates in a pressure relief valve 69 which maintains thedesired pressure in the 'conduit 61.

The conduit 61 extends through safety latchl valve casing 10, to be casing 13 is provided with a bore into which is pressed valve sleeve .14 having a plurality of sets of radial ports 15, 16, 11, 18, 19, 80 and 8| formed therethrough. Each of the sets of 'radial ports are connected by means of a similar circumferential groove 82 formed in the exterior of the sleeve or bushing 14. Extending through a bore in the bushing 14 is a spool-'type valve 83 having piston portions 84,` 85, 86 and 81 between which are formed cannelures 88, 89 and 90. The cannelures in different positions of adjustment of the valve 83 are adapted to connect various of the sets of radial ports. The valve casing is provided with a pair of drilled ports 9| and 92, the former connecting the ports 15 and 19 while the latter connects ports 11 and 80.

The pipe or conduit 1| above referred to, terminates in the drilled port 92. thereby supplying the hydraulic medium under pressure to the radial ports 11 and 80. Connected with the radial ports 16 is one end of a conduit or pipe 93, the other end of which terminates at one end of the cylinder 54. The port 18 has connected with it one end of a conduit or pipe 94 which terminates at the other end of the cylinder 54. From this it will be seen that with the valve -83 in its extreme left hand position the pressure entering the ports 11 will be connected by the cannelure 89 with the ports 18 and the conduit or pipe l94 for directing the pressure to the left hand end of the cylinder, as seen in Figure 24, while with the valve in its other or right hand position the hydraulic pressurein the ports 11 is connected by the cannelure 88 with the ports'16 and the conduitor pipe 93 for directing the pressure to the right hand end of the cylinder. With the valve in the neutral position, as seen in Figure 18, the pressure inl the ports 11 is cut off or blocked while the pressure in the ports 80 is connected by the cannelure 90 with the ports 8| and a pipe or conduit 95 thev purpose of which will be described in detail later.

The valve 83 is adapted to be power shifted for which purpose the ends of the bushing bore are closed by guide sleeves 96 and 91 through which respectively shift piston plungers 98 and 99. Let into the ends of the valve bushing or sleeve are plugs and |0| each of which is provided with a chamber in communication with the ends of its respective piston plunger. Axially through the plugs |00 and |0| `is a threadedperforation for pipes |02" and |03 respectively terminating at a pilot control valve indicated generally in Figure 24 by the numeral |04. This valve |04 is shown structurally in Figure I0, and comprises 4a, bracket or casing |05 secured to the `forward y or front surface of the bed 30. Th`e bracket |05 has formed therein a bore into which is pressed a bushing or sleeve |06 having formed therethrough a plurality of sets of radial ports |01, |08, |09, H0, H2, H3, ||4, H5', H6, ||1 and H8, each set of ports being connected by a similar circumferential groove ||9 formed 4exteriorly of the sleeve |06. Extending through the bushing bore is a spool or piston type valve |20 having piston portions |21, |22,y |23, |24, |25 and |26 providing cannelures |21, |28, |29; |30 and |3i. The cannelures are adapted fto connect the radial ports in different combinations depending upon the position of the valve. The conduits |02 and |03 respectively terminate at the radial ports |09 and Iii.

The low capacity, low volume pump 42 is employed for supplying the power to the control circuit and among other things, as will later appear, for shifting the table reversing valve and, as seen in Figure 24, this pump has a suction pipe |3 2 extending into .the sump or tank 66. From the other side of this pump is the pipe or conduit |33 from which the branch conduit |34 takes off to a pressure relief valve- |35 for maintaining the desired pressure in the control circuit. Branch pressure control conduits |36 and |31 are also taken from the pipe or conduit |33 and respectively terminate at the ports ||0 and 6 in the pilot valve bushing |06. The termini of branch return or exhaust conduits |38 and |39 extend respectively from the ports |01 and ll8'and empty'into the main control return conduit |40. Also emptying into the return control conduit |40 arebranch conduits |4| and 42 respectively connected with .the ports |013 and ||4. Connected with the ports |08 is a conduit |43 which has its other terminus connected with the cylinder conduit 94 while connected with the port ||2 is the terminus of a conduit |44terminating in the cylinder conduit 93. 'In-the conduits |43 and |44 there is placed a hydraulicresistance coil |45 and |46 thereby maintaining a pressure in the portion of the conduits |43 and |44 adjacent the cylinder conduits 93 and 94, the purpose of which will be described later. The ports ||5 and ||1 have respectively connected with them one terminus of conduits |41 and |48 which exten to a valve shifting cylinder for controlling a `valve to be subsequently described..

The pilot-valve |20 has integral therewith and extending therefrom a valve stem |49 in hich vis formed a notch |50 receiving the ball end |5| of a valve actuator or shifter member |52. The valve actuator or shifter member |52 is keyed or otherwise secured to a shaft |53 rotatably journaled'innthe housing or bracket 1| 05 and has its opposite ends walls of the said housing or bracket. T01 the outer projecting end of this shaft |53 is a man- ,ually actuable lever |54 whereby the saidshaft may be. manually oscillated for manually. shifting the valve |20. To the inner projecting end of the shaft |53 is secured a flipper |55 having ^diametrically projecting arms |56 and |51 which `are disposed in spaced parallel planes for operation thereon by dogs carried by the table 32. The table 32 is, therefore, provided with a T-slot |58 'extending' lengthwise thereof for clamping in ad- ',justable positions thereto the dogs |59 and |60. Each of the dogsis provided with a c am face |6| adapted to engage with a roller |62 carried by the extreme ends of thc arms |56 and |51. From this it will be seen that the shaft |53 may be oscillated` for correspondingly i actuating the valve shifter |52. by power means as ell as by the manual lever |54. J

.The pilot valve |20 is adapted to have four po- `sitions, namel shown in Fi e l0, Va neutral left hand position, shown in Figure 24, a neutral right hand posi-A tion, and an extreme right hand position. In order to hold the valve in itsseveral positions, the valve actuator |52 is provided with a pair of notches |63 and |64 co-operating with a load and nre dog or detent |65 whichv is pivoted at |66 interiorly of the housing |05. The notches |63 and |64 are connected by cam shaped walls and in order to maintain contact between the nose |61 of the dog or detent |65 with the cam walls, the dog has secured to it one end of a spring |68, the other end of which is anchored to a fixed part of the housing or bracket |05. The, dog or detent |65 co-operates with the notches |63 and |64y for determining and holding the valve |20 in either of its extreme hold the valve in its other two, neutral, positions, the waive shifter has formed thereon centrally thereof a lug |69 co-operating with the nose |10 of a latch |1|. The latch |1| is pivoted at |12 an extreme left hand position.l

positions. In order to projecting beyond the lateral to a bracket |13 secured to the housing |05. Be-

low the pivot th latch |1| has a tongue |14 abutting a small piston |15 disposed in a cylinder formed in the bracket |13. Behind the piston |15 the bracket |13 is provided withea port `for the one terminus of a conduit orpipe |16 which terminates in a valve ing of a valve indicated generally by the n eral |11 and operated by the ram, as will be later described. To hold the tongue |14 of the latch |1| against the piston |15 there is provided a spring pressed plunger |18 which abuts on its other end against the wall of the housing or bracket |05.

In practice the pressure is cut off from the conduit |16 so that `the spring plunger |18 then holds the nose |10 of the latch in position to engage the lug |69, thereby limiting the movement of the pilot valve |20 from either of its extreme positions toV one of its neutral positions.

The operation of thel pilot valve is as follows: After a work piece has been moimted .on the table A these two lines so that the pressure acts on the piston pllmger 98 for shifting the valve to the position shownin Figure 18 and actuates the table piston and table in the direction as above described. The movement of the table 32 continues until one of the dogs |59 or |60 engages its arm |56 or |51 thereby rotating the shaft |53 to a position for disposing the pilot control valve in one of its neutral positions. At this time the pressure is cut off of the latch actuating piston |15 so that the spring plunger |18 lowers the latch in position to engage the valve actuator lug and hold the valve in its neutral position. The valve is then in position to connect the pressure in the ports ||0 with the ports in addition to the p orts |08 and |09. This then supplies pressure to the conduits 43, |03 and |02, thereby neutralizing the table reversing valve or shifting the said valve to the position shown in Figure 24.

'I'he shifting of the pilot valve by the table dogs |59 and |60 takes place just before the table engages its positive stop and thereby stops the movement of the table by the main actuating pressure. Since the main actuating pressure is now cut off, the table is then slowly shifted into engagement with'the said stop by the pilot valve fluid pressure passing through the choke coils |45 and |46, depending upon in which direction the table is moving. By this construction there is no possibility of the table forcibly bumping its stops and subjecting the entire machine to repeated jars. After the table engages the stop it is held there against during the breaching or machining operation by the pilot pressure bleeding through the choke coils into the ends of the cylinder. After the work piece has been conrpleted the manually actuable lever |54 is actuated to its other extreme position for reversely shifting the pilot control valve and reversing the movement of the table for aligning the second work station ofthe table with the tools Just prior to the alignment of said second work station with the tools, the other of the dogsl |59 or |60 operates the other of the arms |56.or |51` for shifting the pilot control valve toits second neutral position, thereby again centralizing the table reversing valve and` maintaining a pressure in the other table piston conduit, namely 93, holding same against the second adjustable stop.

As was noted above, the breaching tools are carried by a ram 35 .which is actuabie relative to the column along the ways 34. The ram isheld against and positioned relative to the ways 34 by meansiof inner gibs |18 and |80 and outer gibs |8| and |82. The ram 35 has secured to it a lug |83 through which is formed a perforation for the reduced portion |84 of a piston rod |85. 'I'he piston rod |85 extends through a cylinder head and stumng box |86 The cylinder |81 is closed at its other end by a head |88 and operable through the cylinder is a piston |89 secured to the inner end of the piston rod |85. The cylinder head and stuillng box |86 is provided with a port |90 for one terminusA of a pipe or conduit |9| while the cylinder a valve bushing |96.

the'table Pressed into the into a cylinder |81.

head |88 is provided witha similar port |92 for one terminus of a pipe or conduit |93.

For alternately connecting the hydraulic medium with the conduits |9| and |93 there is provided a ram reversing val've indicated generally in Figure 24 by the numeral |94 where the other termini of the conduits |9| and |93 are disposed. The valve |94 is shown structurally in Figure 17 and comprises a casing |95 into which is pressed 'Ihe valve bushing |96 is provided with a plurality of sets of radial ports |91, |98, |99, 200, 20|, 202, 203 and 204, each` set being connected by means of a similar circumferential groove 205 formed exteriorly of the bushing |96. Extending through the bore in the bushing |96 is a spool type valve 206 having piston portions 201, 208, 209, 2|0 and 2|| forming between them cannelures 2|2, 2|3, 2|4 and 2|5.

The valve 206 is adapted in its different positions l 4of adjustment to operatively connect in different combinations the radial ports of the valve bushing. The conduit |93 at its terminus in the valve |94 is connected with the radial ports |99 whileits branch conduits 2|6 is connected with the ports 20|. The conduit 9| at its terminus with the valve |94 is connected with the ports 203. 'I'he conduit 95 extending from the valve 12 terminates at its other end in a drilled port 2|1 formed in the casing 95 with which the radial ports |91 and 202 connect. The conduit 95.is the pressure conduit from the large volume, high pressure pump 43 connected through the table reversing valve 12 so as to connect the pressure with the ram only when the table is in the proper position for aligning the work with the tools.

V'Ihe ports |98 and 200 each have connected with them a branch return conduit 2|8 and 2I9 in turn connected with conduit 220 emptying into the conduit 22| which terminates in the return or exhaustr conduit |40, above referred to. Connected with the ports 204 is one terminus of a conduit-222 which terminates in a valve indicated generally by the numeral 223 and is adapted to maintain a back pressure on one side oi.'

the ram piston.

and 225 through which are shiftable pistonv plungers 226 and '221. 'I'he bushing ends are closed by plugs 228 and 229 forming interiorly thereof chambers in communication with the ends of their respective piston plungers. The plug 228 has secured init one terminus of a conduit or pipe 230'which terminates at its other end in the ram pilot valve indicated generally by the numeral 23|. The other plug 229 has also secured'to it one terminus of a pipe or conduit 232 which likewise has its other terminus in the valve 23|. 1

The ram pilot control valve 23| is shown structurally in Figures 12, 13 and 14 and as there shown comprises a casing 233 adapted to be secured to the outer side of the column just above casing 2331s a valve bushing 234 having formed therethrough a plurality oi' sets of radial ports 235, 236, 231,238 and 239, each set being connected by a similar groove 240 formed around the exterior of Athe bushing 234.. Shiftable through the bore of the bushing is a spool type valve having piston portions 24 I 242, 243 and 244 forming thereby cannelures 2.45, 246 and 241. 'Ihe cannelures are adapted in 5 The ram reversing valve 206 is adapted to|be -4 shifted to its several positions by hydraulic power different positionsof adjustment. of the valve to connect diierent sets of radial ports. The pipe orconduit 236 from the plug 226 has its other terminus connected with the ports 236 while the conduit or pipe 232 has its other terminus con-i nected with po 236. The ports 235 and 233 are connected th the termini of branch discharge conduits or pipes 246 and 243 which have their other termini connected with the discharge pipe 22|. The ports 231 are connected with the terminus of a branch conduit or pipe 253 extending from the conduit or pipe -|41, previously referred to, that terminates in the ports ||5 of ther table pilot control valve |64. The ram pilot valve is adapted to have three positions, namely, to the extreme right, as shown in Figure 24, to the extreme left and an intermediate position, as shown in Figure 12. When the pilot valve is in its rightl hand position, as shown in Figure 24, the 'pres-f sure at' the ports 231 is connected by the can` nelure 246 with the pipe 232 for directing the pressureagainst the piston plunger 221 and l thereby actuating the ram reversing valve |34 to its extreme right hand position and connecting the main operating pressure in the branch conduit 262 through the conduits 2 I6y and |33 to the upper end of the ram piston for causing same to move downwardly and actuate the tools relative to the work. With the -pilot valve in its left hand position the pressure'in'the conduit 231 is connected with the conduit 236 for acting on the piston plunger 226 and thereby shifting the reversing valve I 34 to its left hand position `and connecting the main pressure through the conduit |3| to the under side of the ram piston and effecting the elevation thereof or the withdrawal of the tools with respect to the work. When the pilot valve 23| is in its central or neutral position, the pressure in conduit 256 is connected simultaneously with the pipes or conduits 236 and 232 thereby acting simultaneously on the piston plungers 226 and 221 for centralizing the reversing valve and connecting the main pressure in the port |31 with the branch return conduits 2 I3 and 226 and the main return conduit 22| thereby holding the piston in its stationary position, which during the operation of the machine is in an elevated or raised position.

In order to shift the valve 24| it has projecting from it a stem 25| having formed therein a notch 252 receiving. the ball end 253 of a valve actuator 254. -The valve actuator 254 is keyed or otherwise secured to a shaft 255 which extends through and beyond a hollow extension 256 of the valve casing or bracket 233. Secured to the shaft 255 on one side of the hollow extension 256 'is a manually actuable lever 251 whereby the said shaft and valve actuator may be manually operated. Secured 'to the shaft on the other side of the hollow extension 256 is a clevis 256 bea link 266 for connection with dog actuated means, as will be described in detail later. To-

properly position the pilot valve-24| the valve actuator 254 is provided with `three notches 26|, 262 and 263 which co-operated with` the nose 264 of a detent 265. The detent 265 is pivoted at 266 within the casing hollow extension 256 and in order to maintain contact between the valve actuator and detent nose the detent has secured to it one end of a, spring 261, whose other end is anchored to a ilxed part of either the casing 233 or the hollow extension 256.

The valve actuator is operated in one direction by hydraulic power means which includes a cylinder 266 formed in the casing or housing 233 below the pilot valve 24 Disposed within the cylinder is a piston 263 having a key or pin connection at 216 with the cylinder restraining any roandlinsuring its axial movement through-a given plane. The piston 263 is provided intermediate its ends with'an elongated aperture 21| Zin which is pivoted as at 212 a dog 213.v A spring 214 having a seat in the piston 263 and dog 213 is provided for maintaining the dogI ina definite posi-1 tion with respect to the piston aperture.-l To -limit the movement ofthe dog about its :pivot under the -inuence of the spring 21,4y the said dog is provided with an abutment 215 adapted to engage the rear wall of' the aperture 21|. By this construction the dog 213 is normally held in a position to engage a depending tongue 216 on the valve actuator- 254. From this -it will be seen that movement of the piston 263 to the left, as seen in Figure 12, will cause the dog 213 to .engage the tongue 216 and-move the valve 24| to the right. j In order to shift the piston the cylinder is closed at opposite ends by means of caps211 and 216 in each of whichis `formed a port respectively receiving the termini of conduits or pipes |41 and |46 extending from the pilotjvalve |64, above referred to. Y

The ram pilot valve is adapted .to be .actuated in its other direction by power means through the co-operation of the movement of the ramV tative movement on the part of the piston -263 262- is journaledin a bracket 263 secured to the side of the column above the valve housing or bracket 233. The shaft 262 projects beyond the housing 263 and has pinned or otherwise secured thereto a flipper 264 having arms 265 '.and'266 lying in spacedparallel planes and adapted to be engaged by ram dogs 261'and 266. For this' pur.- p'ose the ram has Vsecured thereto or formed in.- tegral therewith along one side thereof a dograil 263 in which ,is formed a T-slot V23|) for thedog attaching bolts 23|. r

It will be noted that the upper 'ram dog 261 is higher and has agreater throw than the ram dog 28s sd that it throws the flipper. a greater distance than does the dog 266. For this reason thegd'og 261 may be termedfa'reversing dog for throwing the valve actuator 254 and consequently the valve 24| from one extreme position to the other, while thedog 266 may be 'termed a stop dog which merely throws the valve actuator and consequently the valve 24| to its neutral position and thereby stops the movement ofthe ramas above described. For these reasons also the dog 261 is mounted near the upper end of the: ram and comes intov play when the ram `is'near'its lowermost position and the dog 266 is mounted 'play when the ram is in its uppermost position for thereby stopping the movement of the ram piston. i f

The bracket 263 containing the shaft 262 is also near the lower end'of the ram and comes into a valve casing and contains the valve above referredl to by the Inumeral |11, which comprises a valve bushing 232 pressed into the bracket casing 263'.. Formed throughthe valve bushing is a plurality of sets of radial ports 233, 234 .and 235 each ofwhich is connected by asimilar groove 236 liormed exteriorly of the bushing.- It v is with the ports 234 dthat the terminus ofthe conduit |16 from the latch piston connects. The ports 295 are connected with a drilled port 291 from which extends the conduit 298 terminating in the discharge conduit |40. 'Ihe ports 293 connect with one terminus of a pipe or conduit 299` tion the ports 294 and 295. Behind the valve 300 y is a spring 302 normally urging the valve to the limit of its movement in a right hand direction, as seen in Figure 15. The limits of movement of the valve are determined by a keyway 303 and dog nosed screw 304. .f

With the parts in the position shown in Figure 15, the pressure in the ports 293 is connected withthe conduit |16 thereby urging the latch piston forwardly to'disengage the latch and lug on the table pilot valve actuator so that the said valve may be thrown to either of its extreme positions, while with the valve in the position shown in Figure 24, the pressure 'in the ports 293 is shut off thereby permitting the spring loaded plunger |18 to hold the latch in position to prevent movement of the valve actuator and consequently the movement of the table control pilot valve. Since it is only desired that the table control pilot valve be free for movement when the ram is in its 4 uppermost position, the valve 300 is shifted to its free position only when the ram is in the upper position. For this purpose the dog rail 289 of the ram has secured to it a cam 305 havinga cam face 306 adapted to engage the cam nose 30,1 formed on the end of the valve 300.

From the foregoing it will be noted that the table and ram are interlocked in such a relation as to permit the movement of the table only when the ram is out of the way and to prevent descending or ascending. A

The back pressure valve 223 is shown structurally in Figure 17 and as there shown comprises a casing 308 secured in any desirable manner to the movement-of the table when the ram is eitherl the ram reversing valve casing |95. Pressed into' the casing 308 is a bushing 309 having formed therethrough a plurality of sets'of radial ports 3|0, 3|| and 3|2, each set being connected by a similar circumferential groove 3|3 formed exteriorly of the bushing. Disposed in a portion of the bore inthe bushing is a piston type valve 3|4 having formed thereon pistons 3| 5 and 3| 6 forming between them the cannelure 3|1. Extending through the remainingv portion of the bore in the bushing is a spring 3| 8 which abuts on one end of the valve 3|4 and on the other end with an adjustable abutment, here shown as a headed screw 3|9. 'I'he abutment or screw 3 |9 is threaded through a plug r320 threaded into the end of the bushing 309, the outer or free end of the screw 3|9 being enclosed within a cap 32| in turn threaded on the end fof the plug 320. 'I'he other end `of the bushing bore has threaded into it a ferrule 322 through which is formed a port 323 for one terminus of a pip`e or conduit 324.

Connected with the ports 3 0 isone terminus of a pipe or conduit 325 having its.other terminus connected with the pipe or conduit 324. The

A other end of this conduit or pipe 324 terminates at one end of a check valve 326. The conduit 325 has included therein an hydraulic lresistentie 01' choke coil 321 and the conduit or pipe 324 also choke coil 328.

The other side of the check valve 326 has connected with it one terminus of a pipe or conduit 329 which has its other terminus connected with the forward -or feeding main pressure conduit |93 which extends to-the upper side of the ram piston: Included within the pipe or conduit 329 is an hydraulic resistance or choke coil 330. 'Ihis mechanism is employed to relieve the back pressure on the ram piston when the ram is working under heavy stresses, that is, during a heavy broaching cut, as will be later explained more fully. l

Shunted between the conduit 325 and conduit 222 is a pipe or conduit 33| having therein an hydraulic resistance or choke coil 332. Also Shunted between the conduit 222 and conduit 324 is a pipe or conduit 333 having therein an hydraulic resistance or vchoke coil 334. The chokev coil 334 is of a higher resistance than the choke coil 332 whereby the ow through the coil 332 will befreer and result in a normally Vhigher pressure in the conduit 325 thanwill be through the coil 334 and conduit 324. Further, the ports 3 I0 have connected with them one terminus of a conduit 335 in which is placed an hydraulic resistance or choke coil 336. This choke coil allows a bleeding of the hydraulic uid from the chamber containing the spring 3|8 and causes the valve 223 to act as a diierential-balancing valve, that is, ito be operated ,by a difference in pressure on either side o1' the valve.

The operation of this valve is as follows: With no pressure on the` valve spool 3|4 the spring 3|8 would shift it to a position for substantially shut- -ting oil any flow through the ports 3|| thereby ucreating a back pressure in the pipe or conduit 222. The ilow in this return or exhaust pipe 222 would therefore divide into the conduits 33| and 333 thereby flowing through thehydraulic resistances or choke coils 332 and 334 to the opposite ends of the valve. The resistance 334 is so proportioned with respect to resistances 332 and 336 combined with the spring 3|8 as to position the valve 3|4 to uncover the ports 3| to allow the escape oi.' the fluid from the return pipe 222 at the desired or most eiilcient cutting rate. The broaches will continue to operate at this rate and there will be no shifting of the valve so long as the parts continue to function smoothly, that is, so long as the ram does not encounter ay heavy work 'resistance or does not tend to advance at a faster rate of' speed.

In the event the piston and ram tend tc coast ahead, it will result in a surge of fluid being discharged through the outlet conduit. This increased ow will also ow through the choke coils 332'and 334 and since the coil 332 is of a lower resistance than 334 a greater pressure. will be built up on the spring end of the valve, which,

combined with the force of the spring 3|8 will vshift the valve 3| 4 to the right, thereby further restricting the flow through the ports 3|| and substantially instantaneously stopping any coasting ahead of the ram and consequently the up a pressure in excess to the increased pressure in the spring chamber and thereby again uncover a;oo2,f9a4

the ports 3I| to their normal opening thereby permitting a continuation of the descent of the breaching tools at their normal rate. It -should be noted that this shuttling of the valve 3|4 takes place almost instantaneously and without noticeable eifect on the movement of the breach ram and that the shuttling thereof may be continuous or intermittent and depending on the nature of the work being operated upon.

l In the event the broaches encounter a heavy work resistance orv are working under heavyL stresses as when taking a heavy cut it is desired that the back pressure on the ram bematerially reduced, if not entirely eliminated, 'since under coast ahead the mechanism these circumstances the ,back pressure will not be needed. At this time the pressure in the conduit would build up above the maintained back pressure and would force the uid through lthe resistance or choke coil 330'into the conduit 329. The fluid in this conduit would have Va pressure great enough to open the one way check valve 328 and thereby enter and flow through the pipe or conduit 324. The fluid would then ow through the resistances or chokecoils 321 and 328. The fluid flowing through the choke coil 321 would have` a relatively easy path of escape by way of the conduit 325, ports 313, conduit 335 and choke coil 336 as well as by way ofchoke coil 332, conduits 33| and 222, ports 3|| and conduit 22|, while the fluid forced to new through the relatively higher resistance or choke coil l334 before it can scape. This results then in a higher pressure aga st the end of the valve, opposite to the spring, thereby forcing said valve against the resistance of spring 3|8 andl substantially uncovering the exhaust ports 3| I and reducing the back pressure against the piston ram. If, however, the work resistance drops thereby tending to cause the broaches to above described will immediately come` into play for again cuttin down on the ow throughthe exhaust ports 3| l.

From the foregoing it will now be appreciated that the back pressure valve is operated by agdiff ference in pressure on opposite sides thereof and is' in eect aback pressure differential valve. It is to be understood that this valve may be replaced by any other type of valve that functions as above described without rendering the machine inoperative, in fact, this valve may bea valve having different areas exposed to different pressures which are determined by the choke coils 332 and 321 on one side thereof and by choke coils 334 and 328 on the other side.

From the foregoing it will be seen that a constant back pressure is maintained on the ram piston thereby insuring the movement of the tools at a constant, uniform rate while operatingA upon a work piece. It willI further be noted that the tools while-under heavy work resistance have the back pressure on the piston relieved so that it is not necessary to attempt to carry exorbitant pressures on the pushing side of the piston, which would be ruinous upon cessation of the worky resistance. It will be further noted that as soon as the resistance is lowered the back pressure'valve immediately comes into play for again establishing a back pressure and controlling the y ovement of the ram and tools.

As in all hydraulic systems when the parts are stationary, and especially is this true` with heavy units, the fluid on one side of the piston tends seep out and return to the sump or tank. In

the case of the machine of this application this flowingy through the choke coil 328 would be' materially restricted by being would cause a gradual dropping of the rampiston instead of remaining stationary at the upper end of its stroke. In order to overcome this, a small amount of iluid is being constantly fed into the cylinder and the means for accomplishing this includes a pipe or conduit 331 having its one terminus connected kwith the pipe or co'nduit |3| to the lower side of the ram pistonand having its other terminus connected with the pipe or conduit 299 which in turn connects with the discharge pipe of the low volume, low pressure pump 42. In the conduit 331 is an hydraulic resistance or choke coil 338 whereby the volm and presthe pressure conduit or pipe |93 therefor'hasl connected with it one terminus of a conduit 338,

the other terminus of which is connected with i the pipe 331 between the coil 338 and the conduit |9|. In the pipe 339, is an hydraulic resistance or choke coil 340 for reducing the pressure therein since the pressure to be delivered on the upper side of the piston through the conduit |83 needs to be below the pressure on the under side of the 4piston dueto the differential in' areas exposed. To further insure the operation of these parts and in order to drain off an excessive amount of fluid' supplied to the pipe |98 through the pipe 338, the said pipe 339 has connected with it one terminus of a drain pipe. 34| which has its other g rod, ram and broaching tools, the said parts will tend to descend when the pumps are shut off, namely over night or at other times when the machine is shut down. This would lead to considerable difiiculty if the operator were not particularly careful in seeing that the ram was at its upper limit of `movement before operating the machine. In order to avoid these dimculties and the possibilit-y of a' wreck, there is provided a safety locking mechanism operable whenever the machine is shut down. This mechanism has been previously referred to and is indicated in Figure 24 by the numeral 13. lThis safety latch or locking mechanism is shown structurally in Figures 5 and 6 and comprises a casing member 343 secured to the right hand side of the column, as seen in Figure 1. Within the casing 343 is a valve bushing 344 having formed therethrough a plurality of sets of radial ports 345, 346 and 341. I Each of the sets of radial ports are connected together by a circumferential groove 348 formed in the exterior of the bushing. Mounted within the bore in the bushing 344 is a piston type valve 343 having piston portions 353 and forming `between them a cannelure 352. The bore through the bushing 344 is closed at one end by a plug 353 through which is formed a port 354' for one terminus of a pipe or conduit 385. The conduit 355 has its other terminus connected with the pressure conduit |33 from the low pressure, low volume pump 42.

In one position, as shown for example in Figure 6, the valve connects the main pressure line 81 from the high volume, high pressure pump with a discharge conduit 356 which extends from' the ports 345 to the sump or tank 66 while in its second position, shown in Figure 24, it connects the pipe 61 having its terminus at the ports 346 with the conduit 1| which has its terminus connected with the ports 341. i

The lower end `of the piston valve 35|, as seen in Figure 6, contacts withone arm 351 of a bell crank 358 secured to a shaft 359 jpurnaled in the walls of the casing 343. The other arm 360 of the bell crank 358 is ball shaped and adapted to be received in a notch 36| formed in a latch plunger 362. The latch plunger 362 is mounted for axial movement in a bracket 363 secured to the side of the column andcompletely enclosed byfthe casing 343. The latch plunger 362 is provided with a counterbore in which is disposed a spring 364 contacting on one end with the base of the counterbore and on the other end with an adjustable abutment, here shown as a screw 365 threaded through the outer wall of the casing 343. 'I'he inner end of the latch plunger 362 is formed in the shape of a locking pawl 366 adapted to be inserted in the space between rack teeth 361 formed in rack bar 368. The rack bar 368 being in turn secured to the side of the ram 35.

The operation of these parts is as follows: When the pumps 42 and 43 are started and as soon as suiiicient pressure is built up therein, particularly the low pressure, low volume pump, it flows through the conduit |33 to the conduit 355 for urging downwardly the piston valve 349, as seen in Figure 6. This movement of the piston valve downwardly actuates the bell crank 358 for withdrawing the locking plunger 362 and at the same time disconnects the pressure in the conduit 61 from the return conduit 356 and connects said pressure with the main operating pressure conduit 1|. If for any reason the pressure drops in the conduit |33 the spring 364 will immediately expand forcing the piston valve 349 upwardly and connecting the main pump 43with the conduit 356 and at the same time interengaging the pawl tooth 366 with the rack teeth of the rack bar 368 and thereby locking the ram in Whatever position it may be and preventing a dropping or falling thereof.

Incase of an emergency, the locking pawl may be manually actuated to engage with the' rack, for which purpose the bell crank shaft'359 extends beyond one wall of the casing 343 and has its extended portion formed to have an angular cross section for the reception of a manually actuable lever. Ihis angular portion is shown in Figure by the reference character 369.

The ram 35 is provided in its forward face with a channel 3-10, see Figure 4, thereby providing arms 31| and 312. Near the lower ends of the arms 31| and 312 they are provided with a transverse groove or slot 313 in which is disposed the lateral lugs 314 and 315 of a tool head 316. The head 316 has its body portion disposed within the channel 310 and the said head is pierced by four y holes, as shown in the present application. Rei celved in the said holes are the reduced ends or tangs of four broaching tools 311. It isto be understood that other work pieces besides that being operated on here may require more or fewer tools, it being wit the purview of this application to utilize as many or as few broaching tools as required.

The broaching tools 311 are guided and backed up during the broaching `operation by suitable guides disposed both above and below the work. The upper guide is shown in detail in Figure 25 and comprises a bracket 318 of a general U-shaped cross section. The'anns 319 and 380 thereof are provided with attachment pads or feet 38| adapted to be secured to the face of the column immediately above the table. The bracket 318 is provided with a pair of apertures 382 and 383 in which is fastened hardened up blocks 384 and 385. Each of the blocks 384 and 385 is provided with a groove or way 386 for the respective broaching tools. It will be noted from Figure 1 that the bracket 318 is disposed in close proximity with the Work supporting xtures so that the broaching tools are adequately backed during the actual broaching or cutting operation.

The bed 30 has a hollow interior and forms the coolant and lubricant supply tank. It has extending therefrom a pump channel 381 connected with the coolant circulating self-contained pump and motor unit 388. The pump unit 388 discharges the lubricant and coolant through a pipe or conduit-389 which extends to a point above, but behind, the table 32. The pipe 389 is connected with a pipe 390 that terminates in a cross connection 39| immediately in front of the upper guide bracket V318. 'Ihe outlet for the cross 39| directly opposite the inlet of the pipe 390 is connected by a nipple 392 with the port 393 formed in the bracket 318. The port 393 has four lateral branch ports 394 extending therefrom and respectively discharging coolant onto the teeth of the broaching tools just before and while they are passing through the work. 'Ihe lateral openings of the cross 39| are connected by pipes 395 and 396 with ports 391 and 398 formed in the bracket 318 parallel with the port 393 but on the other side of the broach guides 384 and 385. 'Ihe ports 391 and 398 are each respectively connected by a pair of branch ports 399 and 400 with the broach guideways 386 and lubricate the broach during its passage through the said guideways.v

From the foregoing it will be noted that the contacting surfaces between the broach tools and the guideways formed in guide blocks 384 and 385 are adequately lubricated simultaneously with the supply of coolant to the tools and work during the tooling operation. It should be noted that the coolantfemployed in the instant application is a lubricating and cutting oil.

As was set forth above, it is contemplated by the present application to utilize two work loading and clampingxtures, ,which are alternately g rought into position to have the work carried thereby operated upon by the tools. These xtures are the same in all respects being merely duplicates of one another and it is, therefore, deemed suillcient if but one of them be illustrated and described in detail. The said fixture is disclosed in Figures 19 to 23 and as there shown comprises a main or base casting 40| secured in any desirable manner to the upper surface of the Work table 32. The,base 40| is adapted to sup@ guide and backing port two work pieces for simultaneous opera" tion thereon by two of the broaching tools and includes means for roughly positioning the work and subsequently accurately centralizing and clamping the work in position. The positioning meanscomprises a rib 402 secured to the base 40| andA having projecting from each side thereof locating pins 40.3 and '404. The pins 403 and 404 are adapted to enter previously formed holes in the work and align the surfaces to be breached in position for the tools. The base 40| is further provided with a pair of back stop pins 405 one for each work piece and, as shown in Figure 22, has a stepped seat 406 formed thereon for the venience, the axes of gagement with the tinue until the clamping operation,

'engage the latch pin 42s with work. The backing stops 405 co-.operate with the locating pins 403 and 4 04 in positioning the work.

After the work pieces have been positioned, as just described, equaliz'ing clamps are brought into play and these consist of bell crank arms 401 and 408 which are respectively pivoted at 409 and 4|0 to the base 40|. The arms 401 and 408 respectively have pivoted to them equalizing clamp shoes' 4| and 4 I 2 which actually contact with the work and force same into engagement with the central rib 402. One arm 4I3 of the bell crank 401is engaged at its outer end by `clamping plunger 4|4f in turn engaged by the pushing plunger 4|5. As seen in Figure 19, and for the purpose of conthe plungers 4|4 and 415 are disposed at an angle to one another, thereby bringing the clamping mechanism around to the front of the machine within convenient reach of 4 4 and 4|5 are suitable passages formed in the bracket or cylinder 416 pivoted to the toggle -arm 4|1. Threaded into the bracket 4|6 is a clamping screw .4|,8 contacting on .its inner end with the pushing plunger 4|5 and having secured to its outer end the hand wheel 4|9. The toggle arm 4I1 is pivoted at 42.0 to one end of an arm 42| of the bell cranki408, and-is slidably mounted in a suitable guideway. 422 formed on the upper surface of the plate 40| for axial movement relative thereto.

The operation of the clamping mechanism is as follows: By actuating the screw 4|8 toaxially adjust same to push pin 4|5 into enclamping plunger 4|4 axially, adjusts this plunger toward the arm 4|3 of bell crank 401 urging said bell crank about its pivot toward the work piece. This movement will conshoe thereof engages the free movement and causing the toggle arm 4|1 in Figure 19. The 4l1 to the left actuwork thereupon resisting further of this bell crank to shift to theleft, as seen movement of the toggle arm ates the bell crank 408 aboutr its pivot toward its work piece thereby causing its clamping shoe to engage the work. From this it will be seen that the pressures on the two work pieces are equalized and the work is thereby rigidly clamped in position. f

At the conclusion of the broaching or tooling l the screw 4|8 is backed away to'relieve the clamping pressure on the shoes 4|| whereupon the clamping arms are swungout of the way to permit replacement of the work.- This mechanism comprises the pivoting of the bracket or cylinder 4|6 about the axis of the pivot 423 carried by the toggle arm 4|1. The upper end of the pivot 423 is provided with a slotted head 424 between the arms of which is pivoted a latch 425 having a latch pin 426 adapted to enter a socket 421 formed in the bracket`or cylinder 4|6. The latch 425 is spring loaded for tending to the socket 421. From the foregoing it will-be noted that by re'- leasing the latch the bracket or cylinder 4 I6 may be oscillated about the axis of the pivot 423 in a counterclockwise direction thereby completely removing the clamping plunger 4|4 from engagement with thev arm 4|3 of the bell crank 401. Simultaneously with the operation of these parts a spring, pressed, plunger 428 operating on the second arm 429 of the bell crank 401 oscillates the said crank 401 in a clockwise direction about its pivot 409 for completely removing the clamp shoe 4|| from the proximity of the work. Also simultaneously with this operation `a second ,tion ot the operation here.

spring pressed plunger 430 acting on the second arm 43| of the crank 408 oscillates said crank in a counterclockwise direction about the axis of its pivot'4l0 thereby completely removing the clamp shoe 4 l2 from proximity with its work piece. 5

After the work piece has been securely clamped in position with respect to vthe fixture rib 402, the work is backed from beneath by suitable supporting pins, certain of which are disposed to take the cut thrust of the tools on the work. This mechanism comprises, as shown in the drawings, three pins for each work piece and indicated by the numerals 432, 433 and 434. These pins are duplicated for the second work piece and are actuated by similar mechanism now t@ be described. The backing pins 432 and 433 have their 1 lower surfaces beveled to form cam-faces adapted to engage with cam faces 435 and 436 formed respectively on plungers 431 and 438. The plungers 431 and 438 are respectively backed by springs 439 and 440 received in sockets formed.I in the plunger 438 and a plunger 44|. The plunger 44| is connected to a head or block 442 disposed in a recess 443 formed in the forward face of the base member 40|. The third pin 434 has its lower face similarly formed to engage the' cam1 face 444 of a spring pressed plunger 445 carried by the plunger 446 secured to the block 442. By

reference to Figure 23, it will be noted that the t plungers 44| and 446 are simultaneously actuated i 30 vkeyed or otherwise secured to it a manually actuable lever 454. From the foregoing it will be noted that oscillation of the lever 454 in one direction will cause the backing up and leveling pins to simultaneously engage the work and due to the yieldable connection of the plungers will equally act on the work. It will also be noted that due to the pin and slot connection between the plungers, oscillation of the lever in the opposite direction will ,release the backing up and leveling pins. i

It is believed in view of the foregoing thatthe complete operation` of the machine should be readily understood without'a detailed exp1ana It should be noted, however, that the work supporting table is adapted to support two work centralizlng and clamping fixtures or mechanisms which are adapted to be alternately brought into position for operation thereon. It should also be noted that when the work supporting table is operated to present one of its fixtures to the tools the machine is in operation and will continue until that piece is finished and the tools returned to their normalinoperative position. It has been pointed out that the parts are so interlocked that the movement of each unit must be completed before the movement of the next unit can be-initiated' and that during the movement of one of the units no other of them can be operated.

What is claimed is:

1f In a breaching machine f the class described the combination with a bed, and a column, of a 75 means inoperative locked member.

2. In a. broaching machine the combination-oi a work supporting table having a.

through its working stroke and returned to said neutral inoperative position.

3. In a. .broaching machine the combination of at the conclusion of its operation.v L,

5. In a broaching machinethe combination of a. work supporting table having a be alternately positioned with b positive means for alternately positioning said Work supports, and hydraulic means for maintaining the table in said alternate positions.

effecting the sequential operation of the said hydraulic means and consequently the operation of the table and ram. .i

8i Ina broaching machine of scribed the combination of a, be'd, a

the class decolumn rising tional dog controlled means carried by the table for actuating said valve.

9. In abroaching machine vvalve for each motor, power their operation, a .reversing each valve, and independent means associated with each of said power means and releasable by the other whereby the said motors are operated in sequential order.

11. In a broaching machine of the class described the combination of a bed, acolunmrising above the bed, a broaching tool ram carried by the column for movement relative thereto, a work supporting table carried by the bed and having a pair of work supports thereon adapted to be alternately positioned with respect to the' ram, aseparate hydraulic motor'for the ram and table for effecting their operation, a' reversing means for shifting each valve, and an interlock between said power means whereby the said motors are operated in sequential order, said interlock comprising a pilot valve operable by the table for energizing the power shifting means in sequential order.

12. In a broaching machine of the class described the combination with`a broaching tool ram movable in a given direction, and a work supporting table movable in a direction angularly related to the direction ofmovementof the ram, of means spect to the ram, independent hydraulic motors for actuating the ram and table, a reversing valve for each motor, power means for shifting each reversing valve, said power means each including a pilot valve, manual means for shifting one of the pilot valves to initiate the movement of either the ram or table, dog means for shifting said valve when its part reaches its operative position to initiate movement of the other part, dog means for reversing the said movement of said other part, and additional-dog means for stopping the movement of said part.

13. In a broaching machine the combination with a bed, a column rising thereabove, a broaching tool ram mounted on the column for movement relative thereto, a work supporting table mounted on the bed for movement in a direction at an angle to the direction of movement of the ram, said table having a plurality of work supports thereon adapted to be individually aligned with the ram, and means for positioning said table and work supports relative to the ram, of hydraulically actuated means for cyclically shifting the ram and table relative to one another, said hydraulic means including separate hydraulic motors for the ram and table, a reversing valve for each motor, means for cyclically actuating said valves for operating the ram and table in sequential order, and means carried by the ram and table for controlling the operation of said valves.

for positioning the rabiewith re- 14.'In a broaching machinethe combination with a bed, a. column rising thereabove, a broaching tool ram mounted on' the column for movement relative thereto, a work supporting table bed `for movement in a direction ram, said table having a plurality of work supports thereon adapted to be individually laligned with the ram,'and means for positioning said table and work supports relative to the ram, of hydraulically actuated means forcyclically shifting the ram and table relative to one another, said hydraulic means including separate hydraulic motors for the ram and table, a reversing valve for each motor, means for cyclically actuating said valves for operating the ram and table in sequential order, Vmeans carried by the ram and table for controlling the .operation of said valves, and manual cycle. c

15. In a broaching machine the combination with a bed, a column rising thereabove, a broaching tool ram mounted on the column for movement relative thereto, a work supporting table mounted on the bed for movement in a direction at an angle to the direction of movement of the ram, said table having a plurality of work supports thereon adapted to be individually aligned with the ram, and means for positioning said table and work supports relative to the ram, of hydraulically actuated means for cyclically shifting the ram and table relative to one another, said hydraulic vmeans including separate hydraulic motors for the ram and table, a reversing valve for each motor, means for cyclically actuating said valves for operating the ram and table in sequential order,`means carried by the ram and table for controlling the operation of said valves, and power controlled locking means for preventing inadvertent actuation of the parts.

1%6. In a broaching machine of the class Idescribed the combination with: a broaching ram and a work supporting table having a plurality of work positions adapted to be successively aligned with the ram, said table` and ram being movable relative to` one another in angularly related directions, of independent hydraulic motors for actuating the ram and table, said hydraulic motors being operated in sequential order, each at the conc ion of the operation of the other, an hydraulic circuit for effecting the operation of said motors, a reversing valve in .the circuit for each motor, power. control means including a second hydraulic circuit for actuating the reversing valves, a pilot valve in said control circuit for each reversing valve, connections between said pilot valves whereby the reversing valves are sequentially operated, manual means for operating one of saidv pilot valves for initiating the cycle, shifting said pilot valve and effecting the operation of said second pilotv valve.

17. In a broaching machine of the class described the combination-with a lbroaching ram and a work7 supporting table having a plurality of work positions adapted to be. successively aligned with the ram, said table' and ram being movable relative related directions, of independent hydraulic motors `for actuating the ram and table, said hydraulic motors being operated in sequential order, each at the conclusion of the operation of the other, an hydraulic circuit for eil'ecting the operation of said motors, a reversing valve in the circuit for each motor, y including a second hydraulic circuit for actuating the reversing valves, a pilot valve in said control circuit for each reversing valve, conne ions between said pilot valves whereby the reversing valves are sequentially operated, manual means for operating one of said pilot valves for initiating the cycle, dog for shifting means for initiating the and dog controlled means for to one another in angularly power control means 

